FINGERPRINT MEGA 2560 CANNOT READ FINGER

Hello everyone i need help with Fingerprint sensor. i use :

/***************************************************
This is an example sketch for our optical Fingerprint sensor

Designed specifically to work with the Adafruit BMP085 Breakout
----> Fingerprint sensor : ID 751 : $49.95 : Adafruit Industries, Unique & fun DIY electronics and kits

These displays use TTL Serial to communicate, 2 pins are required to
interface
Adafruit invests time and resources providing this open source code,
please support Adafruit and open-source hardware by purchasing
products from Adafruit!

Written by Limor Fried/Ladyada for Adafruit Industries.
BSD license, all text above must be included in any redistribution
****************************************************/

#include <Adafruit_Fingerprint.h>
#include <SoftwareSerial.h>

uint8_t id;

uint8_t getFingerprintEnroll();

// Software serial for when you dont have a hardware serial port
// pin #2 is IN from sensor (GREEN wire)
// pin #3 is OUT from arduino (WHITE wire)
// On Leonardo/Micro/Yun, use pins 8 & 9. On Mega, just grab a hardware serialport
SoftwareSerial mySerial(10, 11);
Adafruit_Fingerprint finger = Adafruit_Fingerprint(&mySerial);

// On Leonardo/Micro or others with hardware serial, use those! #0 is green wire, #1 is white
//Adafruit_Fingerprint finger = Adafruit_Fingerprint(&Serial1);

void setup()
{
while (!Serial); // For Yun/Leo/Micro/Zero/...
delay(500);

Serial.begin(9600);
Serial.println("Adafruit Fingerprint sensor enrollment");

// set the data rate for the sensor serial port
finger.begin(57600);

if (finger.verifyPassword()) {
Serial.println("Found fingerprint sensor!");
} else {
Serial.println("Did not find fingerprint sensor :(");
while (1);
}
}

uint8_t readnumber(void) {
uint8_t num = 0;
boolean validnum = false;
while (1) {
while (! Serial.available());
char c = Serial.read();
if (isdigit(c)) {
num *= 10;
num += c - '0';
validnum = true;
} else if (validnum) {
return num;
}
}
}

void loop() // run over and over again
{
Serial.println("Ready to enroll a fingerprint! Please Type in the ID # you want to save this finger as...");
id = readnumber();
Serial.print("Enrolling ID #");
Serial.println(id);

while (! getFingerprintEnroll() );
}

uint8_t getFingerprintEnroll() {

int p = -1;
Serial.print("Waiting for valid finger to enroll as #"); Serial.println(id);
while (p != FINGERPRINT_OK) {
p = finger.getImage();
switch (p) {
case FINGERPRINT_OK:
Serial.println("Image taken");
break;
case FINGERPRINT_NOFINGER:
Serial.println(".");
break;
case FINGERPRINT_PACKETRECIEVEERR:
Serial.println("Communication error");
break;
case FINGERPRINT_IMAGEFAIL:
Serial.println("Imaging error");
break;
default:
Serial.println("Unknown error");
break;
}
}

// OK success!

p = finger.image2Tz(1);
switch (p) {
case FINGERPRINT_OK:
Serial.println("Image converted");
break;
case FINGERPRINT_IMAGEMESS:
Serial.println("Image too messy");
return p;
case FINGERPRINT_PACKETRECIEVEERR:
Serial.println("Communication error");
return p;
case FINGERPRINT_FEATUREFAIL:
Serial.println("Could not find fingerprint features");
return p;
case FINGERPRINT_INVALIDIMAGE:
Serial.println("Could not find fingerprint features");
return p;
default:
Serial.println("Unknown error");
return p;
}

Serial.println("Remove finger");
delay(2000);
p = 0;
while (p != FINGERPRINT_NOFINGER) {
p = finger.getImage();
}
Serial.print("ID "); Serial.println(id);
p = -1;
Serial.println("Place same finger again");
while (p != FINGERPRINT_OK) {
p = finger.getImage();
switch (p) {
case FINGERPRINT_OK:
Serial.println("Image taken");
break;
case FINGERPRINT_NOFINGER:
Serial.print(".");
break;
case FINGERPRINT_PACKETRECIEVEERR:
Serial.println("Communication error");
break;
case FINGERPRINT_IMAGEFAIL:
Serial.println("Imaging error");
break;
default:
Serial.println("Unknown error");
break;
}
}

// OK success!

p = finger.image2Tz(2);
switch (p) {
case FINGERPRINT_OK:
Serial.println("Image converted");
break;
case FINGERPRINT_IMAGEMESS:
Serial.println("Image too messy");
return p;
case FINGERPRINT_PACKETRECIEVEERR:
Serial.println("Communication error");
return p;
case FINGERPRINT_FEATUREFAIL:
Serial.println("Could not find fingerprint features");
return p;
case FINGERPRINT_INVALIDIMAGE:
Serial.println("Could not find fingerprint features");
return p;
default:
Serial.println("Unknown error");
return p;
}

// OK converted!
Serial.print("Creating model for #"); Serial.println(id);

p = finger.createModel();
if (p == FINGERPRINT_OK) {
Serial.println("Prints matched!");
} else if (p == FINGERPRINT_PACKETRECIEVEERR) {
Serial.println("Communication error");
return p;
} else if (p == FINGERPRINT_ENROLLMISMATCH) {
Serial.println("Fingerprints did not match");
return p;
} else {
Serial.println("Unknown error");
return p;
}

Serial.print("ID "); Serial.println(id);
p = finger.storeModel(id);
if (p == FINGERPRINT_OK) {
Serial.println("Stored!");
} else if (p == FINGERPRINT_PACKETRECIEVEERR) {
Serial.println("Communication error");
return p;
} else if (p == FINGERPRINT_BADLOCATION) {
Serial.println("Could not store in that location");
return p;
} else if (p == FINGERPRINT_FLASHERR) {
Serial.println("Error writing to flash");
return p;
} else {
Serial.println("Unknown error");
return p;
}
}

after uploading the code i open the serial monitor and send the ID. But after i put my finger, the sensor cannot detect my finger. anyone can help my problem?? Thank you

Capture.PNG

Do you understand this comment at the beginning of the code

// [color=red]Software serial for when you dont have a hardware serial port[/color]
// pin #2 is IN from sensor (GREEN wire)
// pin #3 is OUT from arduino  (WHITE wire)
// On Leonardo/Micro/Yun, use pins 8 & 9. [color=red]On Mega, just grab a hardware serialport[/color] 
[color=red]SoftwareSerial mySerial(10, 11);[/color]

They also sent say

// On Leonardo/Micro or others with hardware serial, use those! #0 is green wire, #1 is white
//Adafruit_Fingerprint finger = Adafruit_Fingerprint(&Serial1);

How is your sensor connected?

J-M-L:
Do you understand this comment at the beginning of the code

// [color=red]Software serial for when you dont have a hardware serial port[/color]

// pin #2 is IN from sensor (GREEN wire)
// pin #3 is OUT from arduino  (WHITE wire)
// On Leonardo/Micro/Yun, use pins 8 & 9. On Mega, just grab a hardware serialport
SoftwareSerial mySerial(10, 11);





They also sent say

// On Leonardo/Micro or others with hardware serial, use those! #0 is green wire, #1 is white
//Adafruit_Fingerprint finger = Adafruit_Fingerprint(&Serial1);





How is your sensor connected?

I already try that comment too, but it didn't work.